Mr. Smith is wrong, of course. Nevertheless, it is interesting to see him make those kinds of claims. It seems to show that despite alleging that his reasons for joining the Roman communion are "doctrinal," Mr. Smith himself doesn't really understand Rome's doctrines.
Rome itself has, in a fairly official way, explained that the Lutheran view still appears to be within Trent's anathemas:
The major difficulties preventing an affirmation of total consensus between the parties on the theme of justification arise in paragraph 4.4 The Justified as Sinner (nn. 28-30). Even taking into account the differences, legitimate in themselves, that come from different theological approaches to the content of faith, from a Catholic point of view the title is already a cause of perplexity. According, indeed, to the doctrine of the Catholic Church, in baptism everything that is really sin is taken away, and so, in those who are born anew there is nothing that is hateful to God.3 It follows that the concupiscence that remains in the baptized is not, properly speaking, sin. For Catholics, therefore, the formula "at the same time righteous and sinner", as it is explained at the beginning of n. 29 ("Believers are totally righteous, in that God forgives their sins through Word and Sacrament.... Looking at themselves ... however, they recognize that they remain also totally sinners. Sin still lives in them ") is not acceptable. This statement does not, in fact, seem compatible with the renewal and sanctification of the interior man of which the Council of Trent speaks.4 The expression "opposition to God" (Gottwidrigkeit) that is used in nn. 28-30 is understood differently by Lutherans and by Catholics, and so becomes, in fact, equivocal. In this same sense, there can be ambiguity for a Catholic in the sentence of n. 22, ..."God no longer imputes to them their sin and through the Holy Spirit effects in them an active love", because man's interior transformation is not clearly seen. So, for all these reasons, it remains difficult to see how, in the current state of the presentation given in the Joint Declaration, we can say that this doctrine on "simul iustus et peccator" is not touched by the anathemas of the Tridentine decree on original sin and justification.(Responses of the Catholic Church to the Joint Declaration, Pontifical Council for Promoting Christian Unity - bold and underline emphasis added)
Horton provides some probing questions that gently expose some of the problems with Mr. Smith's claims. It's not necessarily the style I would use (nor do I think it is the best style), but I think Horton does a good job within his own paradigm of interviewing.